Respuesta :

AB/LM = AC/LN
4/12 = x+2 / 5x-2
1/3  = x+2 / 5x-2
5x-2 * 1 = (x+2) * 3
5x - 2 = 3x + 6
5x - 3x =  6 + 2
2x = 8
x = 4

AC = x+ 2 = 4+2 = 6